A bid that would have safe-guarded the Ross Sea's pristine eco-system with the world's largest marine protected area has failed.

New Zealand and the United States had proposed a 2.27 million sq km reserve, including a 1.6 million sq km designated no-take zone, but the 25-nation Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) yesterday failed to agree to such a proposal during the final day at its 11-day conference in Hobart, which ended late last night.Minister of Foreign Affairs and Trade Murray McCully told Radio New Zealand good progress had been made during the meeting, but more work was needed to convince some countries to back the compromise.

"I've said consistently, in a response to some of the wild and woolly ideas that have been pushed around New Zealand politics, that getting 25 countries to agree to a marine protected zone in the Ross Sea was going to be a big ask - the real risk was that we'd get no agreement.

"As it's turned out we've seen New Zealand and the US come up with a proposal that I think will eventually get across the line but it's going to take some work and there's been a special meeting called for July next year during which we've got to try to get some countries that don't share our views on conservation values in that region to join us on this thing."

Mr McCully said it was the countries that saw fishing as paramount that held out against the compromise.

He said our delegates at the meeting assured him he did not need to be there to push the proposal.

"I think our team have done a good job over there to be frank - first of all to get agreement with the US on a proposal that I think has a good chance eventually of running but also to try to line up a second meeting next year."

Mr McCully said New Zealand would be well placed to lead the lobbying effort that was needed to ensure agreement by all CCAMLR countries.

It is understood the talks fizzled after fishing nations blocked progress.

"In particular, Russia and China hid behind procedural concerns and made it impossible for even constructive dialogue to occur at the Commission," Greenpeace US oceans campaign director John Hocevar blogged on the Huffington Post's website.

"The Ukraine seemed to forget the conservation mandate of CCAMLR completely, pretending not to know that fishing interests are not the only consideration. Korea and Japan were somewhat less obstructive, but have a long way to go if they want to be seen as part of the solution instead of part of the problem."

Instead, an intercessional meeting will be held in Germany next year.

It was not yet known if New Zealand and the US would again push its joint proposal.

The decision comes despite long-held calls from hundreds of scientists to protect key eco-systems in the most pristine ocean - and one of the last healthy eco-systems of its kind - left on the planet.

Philippa Ross, the great-great-great-granddaughter of polar explorer Sir James Clarke Ross, who discovered the sea in 1841, said the need to protect the sea far outweighed commercial gains which affected the talks.

"If my great-great-great grandfather was alive, he would be baffled as to why there is so much bureaucracy around this," said Ms Ross, who addressed delegates last month.

"It's really simple, but at the end of the day it all boils down to financial gain and everyone wanting a piece of the action."

She vowed to keep fighting "until the entire Ross Sea is safe from fishing".

Kiwi film-maker Peter Young, whose documentary The Last Ocean looked at the race to stop commercial fishing in the Ross Sea, also said establishing a reserve was a "no brainer".

Labour described the failure to agree to one as "the worst possible outcome" of the conference, while the Antarctica Ocean Alliance, which held an 11th hour silent vigil outside the conference, saw it as an "international disappointment to millions who have called for real protection for these near-pristine waters".

Public support for Antarctic marine protection had grown significantly this year with more than 30 international environmental organisations convening and amassing more than 1.2 million calls for large-scale protection, including almost 180,000 people joining the AOA WATCH of CCAMLR.

New Zealand's joint proposal came after it abandoned a previous one with the United States, instead opting for its own proposal which would have offered less protection to the Ross Sea's toothfish fishery.

By last year's catch of 730 tonnes, the toothfish industry in the Ross Sea has a $20 million export value to New Zealand companies.